The bitter fight over unions that has swept across the country in the past year is erupting in Minnesota, as legislators begin toiling over a controversial proposal that would alter the nature and diminish the might of organized labor in the state.

More than 1,000 sign-wielding union workers and supporters poured into the Capitol on Monday, urging legislators to reject a proposed "right to work" constitutional amendment that is turning Minnesota into the latest Midwestern flashpoint in what has become a grinding clash between powerful unions and groups trying to break their grip on workplaces.

"This is going to turn Minnesota into a third-world country," said Mike Riley, a pipefitter from Elk River. "The way people are struggling now, how can they go after the unions?"

But as union workers chanted "Shame on you," supporters insisted the measure is crucial to making the state attractive for homegrown businesses and companies looking to relocate here. They say current union laws automatically raise the costs for businesses in the state. "What this amounts to is a job tax," said Sen. Dave Thompson, R-Lakeville, who is sponsoring the measure.

The Senate Judiciary and Public Safety Committee voted 7 to 6 on Monday to pass the bill on to its next committee stop, ending an emotional four-hour hearing. As the meeting ended, the crowd chanted "We will return." The committee's Republican majority supplied all the "yes" votes, while all DFLers voted "no," joined by Sen. Bill Ingebrigtsen, R-Alexandria, who said he helped form a union when he was a young deputy sheriff.

This was the first action on the "right to work" proposal, which prohibits unions from requiring nonmembers to pay dues or fees, and which generally makes it harder for unions to organize and retain members.

Video (55:56): Public testimony for 'Right To Work'

The Capitol echoed the union tumult that has swept the Midwest since Republican gains in the 2010 election.

In Indiana, a right-to-work bill was signed into law Feb. 1 after months of political stalemate and a walkout by Democratic legislators. In Wisconsin, Republican Gov. Scott Walker pushed through a measure last year to eliminate most bargaining rights for public employees, filling the Capitol with protesters, triggering a walkout by Democrats and a recall effort this year that could cost Walker his job. Ohio adopted a strict anti-public-bargaining law last year, only to see voters overwhelmingly repeal it in a referendum in November.

These battles are bleeding over into the 2012 election and have energized the labor movement, which is a key component of the Democratic Party's coalition.

Supporters want to amend the state Constitution, meaning if the Republican-controlled Legislature approves, the issue would go directly to the November ballot. Voters would then decide whether to make it part of the state Constitution. This two-step process allows Republicans to get around DFL Gov. Mark Dayton, who bitterly opposes the measure, but ultimately has no say.

"It's a misnomer; it's the right to work for lower wages," Dayton said.

Overflow crowd

Union workers and supporters staged one of the largest demonstrations at the Capitol in recent memory. In addition to filling the hallway and stairways outside the committee room, they filled four overflow rooms, where members watched the proceedings on television. Senate Sergeant at Arms Sven Lindquist said there was seating for 650 people in the overflow areas, in addition to those outside the committee room. He said the group was loud and energetic but well-behaved.

There were construction workers, government workers, electricians, cops and teachers -- a bright sea of union-logo shirts under hard hats, fire helmets, safety orange vests and at least one sombrero.

"This knocks down everybody's wages," said Riley, the man under the sombrero.

The protesters kept up an almost nonstop uproar, chanting in shifts as the committee deliberated, falling silent only when union members rose to testify.

"They're trying to take the unions down because of politics," said Minneapolis firefighter Bilal Atiq, watching the committee debate through the locked hearing room doors.

Inside the committee room, the two sides argued respectfully over an issue that has divided states since the 1940s: whether established unions, which cannot compel membership, can require that workers who remain outside the union pay dues or fees to cover the services the union is required to provide them. Indiana became the 23rd "right to work" state, where union membership is generally much lower. In Minnesota, 15.8 percent of all workers are unionized, compared to 11.8 percent nationally and 5 to 8 percent in traditional "right to work" states in the South and Rocky Mountain regions.

The state's largest business associations did not testify, but supporters from the Center of the American Experiment, a conservative think tank, said Minnesota will attract more job-creating businesses if it makes the change.

Supporters said the current law allows unions to take its members for granted, rather than competing for their business -- and their union dues. "Right to work changes the dynamic and gets unions focused on members as customers," said Kim Crockett, head of the Center of the American Experiment.

Workers who disagreed with their unions testified for the bill, which they view as a matter of personal freedom. "I feel my human and civil rights have been violated by this mandatory union membership,'' said teacher Elaine Kollar.

The bill was moved to the Senate Rules Committee, from which it could move to the Senate floor. But the "right to work" so far remains stalled in the House and Thompson said he is not sure if it will pass this year.

Tending to party politics, President-elect Donald Trump is rallying supporters in Louisiana on Friday ahead of the state's Senate runoff election, aiming to pad the Republican majority he will inherit.